Lubricating system for internal combustion engines



c. T. DOMAN -2,366,701

LUBRICAT ING SYSTEM FOR INTERNAL-COMBUSTION ENGINES I Jan. 9, 1945.

1942 2 Sheets-Sheet 1 Filed Aug. 5,

INVENTOR. BY CARL T. yMAm ATTORNEYS j Jan. 9, 1945. Q DQMAN 2,366,701

LUBRICATING SYSTEM FOR INTERNAL-COMBUSTION ENGINES Filed Aug 5, 1942 2 Sheets-Sheet 2 I f 25 1 19.4. II, 2?; l A 7 ,21

n 7 NW/717i 1a 25 INVENTOR CARL T DOMAH Patentecl Jan. 9, 1945 i l v UNITED STA ES PATENTQOFFIC E a 2, 36.6,701 I LUBRICALTINGSYSTEM FOR INTERNAL- COMBUSTION ENGINES 1 can T. Doman," Geddes, N. in, .as signor to Aircooled Motors Corporation, Syracuse, N. Y., a corporation of New York Ap l e i n Au ust; 5, 1942, seriarN 453,685

2 Claims. (Cl.1231-.90)

, has for its object amethod of lubricating and means, as the tubes housing the push rods, for conductingthe excess oil to the movable parts of the valve mechanism, as the rocker arms of overhead valve mechanism and maintaining a reservoir of oil available for splash lubrication.

The invention consists "in theinovel features and in the combinations andconstructions hereinafter set forth and claimed. 1, In describing this invention, reference is had to the accompanying drawings in which like char acters designate corresponding parts in all the views.

Figure 1 is a fragmentary sectional view of a horizontally opposed, internal combustion engine of the valve-in-the-head type. i

Figure 2 is a planview of the head of one of the engine cylinders, the cover or casing for the rocker arm mechanism being removed.

Figure 3 is a fragmentary sectional view, partly; in elevation, taken approximately on lines 3+3, Figure l.

Figure '4 is mean view of one form of hydraulic valve lifter.

I designates a cylinder ofon e bank of cylin ders of a horizontally opposed or fiat engine; 2 the piston workin in thecylinder; 3 the connecting rod; 4 the crank on the crank shaft 5. The crankshaft 5 is suitably mounted in. the

crank case 6 of the engine. I deignates the cam shaft mounted in the crank case and geared to the crank shaft'in any suitable manner. 8 and 9 designate intake and exhaust poppet valvesin the head!!! of the cylinder, these being closed when the opening force of the valve mechanism is released in the usual manner against their seats by springs, as l l. The head is formed with intake and exhaust ports X and Y in any suitable manner. The valves are operated by valve mechanism including movable members here. shown as, rocker arms 12 and I3 suitably pivoted between their ends on the head In and operated through mechanism, as push rods, from the cam shaft.

for the rocker arms l2, l3and this construcis a cover or casing on the head 55 h This invention relates to lubricatingj systems 1 member. l8, which isslidably, mounted in the passage or bore l9 or in the crank casing, an

push rod 5 or H, the chamber in which the tion forming a reservoir or sump for oil, which is splashed during the rocking of the rocker arms in the casing to lubricate the pivotal and other points of the valve mechanism.

I5 designates hydraulic valve lifters, which cooperate with cams on the cam shaft I, the motion of these lifters being transmitted to the rocker arms for the intake and exhaust valves by push rods l6 .and ITI respectively. The con,- struction of the'valve lifters forms no part of this invention, and they are pertinent to this invention,.in so far asthey have a pumping action, and the oil pumped thereby or expelled or leaking therefrom under the pumping action is conducted to the casing or cover I 4. The valve lifter here shown comprises an outer tubular inner cylinder or plunger chamber 2| fixed in the outer memberl8 and having a plunger 22 therein, which thrusts against the end of the plunger works communicating with the interior of the outer member 18 through a check-valve controlled passage .23. The plunger chamber 2! I opens into a second chamber or compartment 24 in the outer member l8 and intowhich the oil discharges or leaks from one side of the plunger 22 tothe other, during the operation of the lifterand the valve mechanism. The outer member. I8 is also formed with inlet passages 25 throughwhich oil under pressure passes from a feed passage 26 in the wall of the crank caseand with ducts 26, 26 leadingtherefrom and open: ing at 121 into the bores in which the valves lifters I5 aremounted; Pressure is applied. to the oil in the passage 28 in any suitable manner. The oil passes from the crank case through the passage 26 and into the valve lifters through the passages 25 and also through the check-valve controlled: passages 22 into the plunger chambers or cylinders 2| where it acts on the plunger to always take up any lost motion that would otherwise occur, due to variations in clearances between the push rods and the rocker arms and the rocker arms and the valve stems, or in other words, to maintain a zero clearance. .As the valves seat under their springs ll, some of the oil will be forced or caused to leak past the plunger 22 into the chamber-24. This leaking action is in effect a pumping action, which is con-- stantly taking place and building up during the operation of the engine, so that oil is being expelledat all times into the chamber 24 and expelled from the bore l9 during the reciprocation of the lifter by the cam shaft.

There are valve lifters for the intake and exhaust valves, one for each, and these are ar-- ranged in the passages 19 and 20 respectively, which are located side by side. The duct 21 is common to the two passages in the valve lifters and is located in the separating wall betweenthe two passages or bores I9, 20.

The head ll] of the cylinder is formed with a laterally or downwardly projecting flange. 2.8 in. the fiat engine construction illustrated, the flange extending beyond the cylinder walls at one side, as the lower side, and being opposed to the portions of the crank case in which the valve lifters are located. The push rods l6 extend through openings in the flange 28 and thrust against the rocker arms l2, l3. The push rods I6, H are enclosed in tubes 29 and 30 extending between the flange and the oppos ng Portion of the crank case and having their ends anchored in the flange and in the crank case, the inner ends being located to receive the oil pumped by the valve lifters and the outer ends opening into the casing I4. The bore for one only of the valve li te s s pr v ded w th a tu n u et 3| to e crank case o h r o l sumo m. whi t e o is pum under p essur o the inlet 2 Thus, du ng he perat n. o t e valve l t s, one o the. valve lifters pumps the excess oil through the tube 29 to the casing M, where it accumulates in ool and o er o s t t e ther tube 30 o h cran case hr ugh e u t 3 T e l spring-seated intake and exhaust valves for the 3 cylinder, a piston, a, crank shaft and a cam shaft, equipment, valve mechanism operated by the cam shaft including movable members, and

hydraulic valve lifters operating said members and operated by the cam shaft, the lifters being pumped by the other valve lifter passes directly V out through the outlet ,3 l. v

Thecasing I4 is provided with a baflie 32 on the lower side thereof. The tubes open into the easing on opposite sides of the, bafile. The ends of the'rocker arms also extend, on opposite sides of 7 the baille. The baflle maintains apool on one side thereof which overflows into the other side and returns through the tube 30. During the action of the rocker arms, the oil of the pool is splashed over the movable members or rocker arms and their bearings and their points of Contact with the valve stems and drains out through the tube '30.

In case more oil is needed, that is, due to the normal leaking of the valve lifter or passage may of the type to wlfiieh oil is supplied under pressure and having a pumping or leaking action during the operation of the engine, the engine being formed with bores in which the lifters work. a ca ing enclosing said movable m mbers, tubes between the casing and the bores for, the valve lifters respe tivel push rods in the tubes for transferring the movements of the lifters to said memb rs r ectively, one tube, only havin are u n o tletadiao nt. the li er, all whereby the oil pu ped b th other lifter is. passed throush th companion. tube to the as ng nd the mem hers th rein. an drains out through the former tube to the return outlet.

A. valve. mechanism. lubricating ystem ior nternal.oornloustionv enginesin uding a cylinoer, pring-seated inta e. and exha st valves. for th cy inde a piston, a crankshaft. and a oam shaft equipment, valv mechanism. operated by th cam shaft includ ng, mova le members. a hydraulic valve litter operating said members and operated by the cam shaft. the lifters being of. t type to which on is supplied under pressure and having. a pumping or leaking aotion. during the o eration oi thev engin th engine being formed with bores in which the lifters work, a ca ing enclosing s id movable members, tubes b tween the c sin and the bores ,for the valve 

